Pilot only stays lit when temp at lowest setting


  #1  
Old 10-21-18, 08:17 PM
A
Member
Thread Starter
Join Date: Oct 2018
Location: Canada
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Pilot only stays lit when temp at lowest setting

I have had my hot water tank evaluated by 2 different repair technicians and they were not able to correct the issue I am having. The pilot will occasionally go out and need to be re-lit, though it has not gone out in a few weeks. The bigger issue is that the temperature has to remain on the lowest setting in order to remain lit for an extended period. If the temperature dial is increased even by a millimetre, then the pilot will go out within the hour.

The heater is an A.O. Smith ProMax, and the control valve(?) is new and was professionally installed a few months ago
Photos here: https://imgur.com/a/2m59ONO

Any suggestions are greatly appreciated!
 
  #2  
Old 10-22-18, 04:31 AM
B
Member
Join Date: Oct 2015
Location: Ct.,USA
Posts: 3,297
Received 308 Upvotes on 273 Posts
Appears control valve status codes should indicate if any of the detectable failures is occurring. Not sure if Control OFF/Pilot Out (no flashing) is an AND or OR condition. Do you have the owner's manual to check. If you are not getting any flashing codes indicating failure, the only other thing I can think of is a chimney down draft blowing out the pilot. Is there a backflow damper on the exhaust pipe?
 
  #3  
Old 10-22-18, 05:15 AM
A
Member
Join Date: Mar 2010
Location: USA
Posts: 4,560
Upvotes: 0
Received 285 Upvotes on 260 Posts
Does the water heater work (burner kick on) at that lowest temperature setting? As opposed to the lowest setting being for "vacation" use?

If hot water usage is very minimal just the pilot light might keep the water heater contents hot.

Could it be that as soon as the burner kicks on it is oxygen starved because the air inlet has tripped closed, in turn because of possible spilled flammable liquid on the floor outside? For water heaters with this fire prevention feature, a replacement gizmo has to be installed in the combustion chamber to hold the air inlet open.
 
  #4  
Old 10-23-18, 06:45 PM
A
Member
Thread Starter
Join Date: Oct 2018
Location: Canada
Posts: 4
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for the reply. Yes, the heater works at the lowest setting and the pilot has remained lit for several weeks without issue. It is not ideal though, and the hot water supply is barely enough for a shower.

So you think it could be an air supply issue?
 
  #5  
Old 10-25-18, 07:47 PM
A
Member
Join Date: Mar 2010
Location: USA
Posts: 4,560
Upvotes: 0
Received 285 Upvotes on 260 Posts
Probably not an air supply or air intake issue in this case. If the flammable vapor protection feature got activated, then the burner will kick off within a few seconds of kick on and the pilot would go out with it.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: